不同位置内外上髁轴线对多层螺旋CT容积再现测量肱骨头扭转角的影响

[目的]探讨肱骨远端不同位置内外上髁轴线对多层螺旋CT容积再现三维重建测量肱骨头扭转角的影响。[方法]收集51根肱骨干标本,行16排螺旋CT扫描,容积再现技术三维重建测量肱骨头扭转角。俯视位观察,肱骨远端内外上髁连线取3种不同方位,求得3组肱骨头扭转角。与二维CT取肱骨远端3个不同平面的肱骨头扭转角进行对比研究。[结果]肱骨头扭转角最小值4°,最大值59.8°,6组肱骨头扭转角数据为(25.5±10.2)°,(25.0±10.8)°,(25.7±10.8)°,(27.3±10.3)°,(26.3±10.2)°,(25.8±10.4)°,经统计学处理6组肱骨头扭转角差异不显著。且二维CT测量肱骨头扭转角时肱骨远端层面越向远端值越小。[结论]肱骨头扭转角变异较大,肩关节假体扭转角设计应个性化;肱骨远端不同位置内外上髁轴线对多层螺旋CT容积再现测量肱骨头扭转角没有影响;俯视位观察肱骨,当外上髁露出呈小三角形、肱骨远端前关节面被肱骨头遮盖重叠的位置是多层螺旋CT三维重建测量肱骨头扭转角的更简单、更快捷而且准确的测量位置。     

多层螺旋CT和MRI测量肩胛盂斜倾角的互补性初探

目的 探讨多层螺旋CT(MSCT)多平面重组(MPR)及MRI测量肩胛盂斜倾角的互补性.方法 收集成人肩胛骨干标本22侧及肩关节防腐湿标本24侧,用16层螺旋CT扫描仪扫描,多平面重组重建肩胛骨并测量肩胛盂斜倾角,得数据A组.收集MRI检查正常的肩关节病例50侧,取其斜冠状位T1WI显示肩锁关节的层面测量肩胛盂斜倾角,得数据B组.进行统计学处理.结果 肩胛盂斜倾角最小值91.10°,最大值118.50°,A、B 2组肩胛盂斜倾角数据分别为101.14°±4.66°和104.05°±7.72°.2种测量方法肩胛盂斜倾角值统计学上有显著性差异(P＜0.05).结论 MSCT的MPR法测量肩胛盂斜倾角与MRI测量值不同,前者略小于后者;MSCT和MRI 2种测量肩胛盂斜倾角方法结合具有重要的应用价值.     

国人肱骨近端三维解剖研究及其对假体设计与植入的影响

目的测量部分国人肱骨近端的三维解剖数据,并与欧美人的解剖数据对比,评估假体设计及假体在术中的定位和安装规范对中国人的适用度。方法正常成人志愿者180例,随机选取单侧肩关节,进行CT扫描,扫描层厚5mm,以1.25mm层厚、0.6mm层间隔进行重建,重建后的图像用Mimics与Imageware软件进行处理,进行三维测量。结果国人平均肱骨全长(29.7±1.9)cm,平均肱骨近端髓腔直径(11.6±1.9)mm,平均肱骨头额状面直径(42.4±4.0)mm,平均肱骨头矢状面直径(40.1±3.9)mm,额状面与矢状面直径比为1.06±0.09,平均肱骨头表面曲率直径(44.6±4.4)mm,平均肱骨头高度(16.7±1.9)mm,肱骨头高度与曲率半径比为0.75±0.07,颈干角平均129.7°±4.3°,肱骨头后倾角平均15.9°±9.2°,肱骨头内侧偏心距平均(5.0±1.6)mm,肱骨头后侧偏心距平均(3.5±1.6)mm。与欧美人相比,只有肱骨近端髓腔直径与肱骨头高度比较,差异无统计学意义,与其他项目比较差异有统计学意义,且国人的肱骨头高度、颈干角、后倾角均与目前手术规范有区别。结论国人与欧美人种的肩关节解剖存在很大差异,应对引进假体进行适当改进,并制定假体在术中的定位与安装标志。     

CT三维重建区分股骨颈扭转角与前倾角

目的:利用CT三维重建技术描述股骨颈扭转角与前倾角,显示二者区别并测量数据。方法:2010年3月至2010年10月,采用CT重建扫描30例健康成人志愿者股骨结构,男15例,女15例;年龄25～65岁,平均(43.66±7.57)岁。进行图像后处理显示股骨颈扭转角及前倾角,用"圆心法"测量扭转角,直接测量股骨颈前倾角。结果:股骨颈前倾角是股骨头颈中心轴线与股骨冠状面的夹角,测量结果为(13.326±6.085)°;扭转角是股骨颈截面的长轴面与股骨冠状面的夹角,测量结果为(31.335±2.079)°。两角度左、右侧比较差异无统计学意义。结论:股骨颈前倾角与扭转角是股骨上段完全不同的两个角度参数,前倾角是线与面的夹角,角尖朝向外下,扭转角是面与面的夹角,角尖朝向后下。     

股骨颈扭转角的CT测量及临床价值

[目的]通过CT成像描述股骨颈旋转角并测量数据,探讨临床价值。[方法]用螺旋CT扫描15个健康成人志愿者双侧股骨上段,三维成像,描述并用二种方法测量股骨颈扭转角。[结果]股骨颈扭转角是股骨颈截面最长径与股骨上段长轴的夹角,"圆心法"测得成角左侧30.00°±3.23°,右侧29.07°±3.65°,股骨颈不同部位及左右侧差别无统计学意义。[结论]三维CT成像能良好显示股骨颈扭转角并测量,"圆心法"测量值理论上更接近真实值。此角度对股骨上端手术操作及内固定设计有参考价值。     

髌股关节紊乱与胫骨扭转畸形的相关性分析

目的 :通过分析髌股关节退变性骨关节病(patello-femoral degenerative arthrosis,PFDA)患者的胫骨扭转畸形与髌股关节在静力及动力条件下排列紊乱的关系,揭示胫骨扭转畸形诱发PFDA的可能机制。方法:自2009年10月至2010年10月,选取PFDA患者50例86膝,男24膝,女62膝;对照组16例23膝,男7膝,女16膝。分别在CT扫描片上测量胫骨扭转角,并测量屈膝30°位时,分别在静力和动力条件下的髌股和谐角及外侧髌股角,经统计学对比分析后,评价PFDA患者的胫骨扭转畸形与髌股关节排列紊乱的关系。进而将PFDA患者按胫骨扭转角大小分为胫骨扭转角过大组(胫骨扭转角≥30°)、胫骨扭转角过小组(胫骨扭转角<15°)和胫骨扭转角正常组(15°≤胫骨扭转角<30°),测量屈膝30°位时,分别在静力和动力条件下髌股和谐角和外侧髌股角,进行统计学处理,分析PFDA患者胫骨扭转畸形与髌股关节排列紊乱的关系,尤其在动力条件下的关系。结果:PFDA患者的胫骨扭转角(30.30±7.11)°,大于对照组(23.10±4.73)°;与对照组比较,PFDA患者有较大的髌股和谐角(13.20±3.94)°及较小的外侧髌股角(12.30±3.04)°。胫骨扭转角过小组和胫骨扭转角过大组在静力及动力条件下的髌股和谐角和外侧髌股角比较,差异有统计学意义(P<0.05)。而胫骨扭转角正常组的髌股和谐角在静力和动力条件下比较,差异无统计学意义;外侧髌股角在静力和动力条件下比较,差异亦无统计学意义。结论:胫骨扭转畸形者多伴有髌股关节不稳,尤其是动力状态下的匹配关系紊乱,是造成PFDA患者髌股关节紊乱的主要原因。CT检测髌股关节及胫骨扭转角,既能提供髌股关节排列的信息和髌股关节的退变状况,又能通过对两者对应关系的分析为临床更好地预防和早期治疗退变性骨关节病提供指导。     

两种股骨扭转角测量方法的比较

目的通过CT法及裸骨投照测量法(以下简称“裸骨法”)测量股骨扭转角的比较,探讨CT测量扭转角的可靠性。方法分别采用CT法及裸骨法测量80个股骨标本股骨扭转角,对测定值进行统计学分析,并作左右两侧比较。结果采用CT法测量的扭转角为11.04°±8.24°(-6.1°～34.0°);裸骨法测量的扭转角为11.27°±8.01°(-5.5°～34.2°)。两者间的扭转角度相差0.23°±1.64°(-4.4°～3.4°),差异无显著性意义(P>0.05,配对样本t检验)。左右两侧对比,差异无显著性意义(P>0.05,独立样本t检验)。结论CT测量法是临床测定股骨扭转角确实可靠的方法,临床上健侧的扭转角可作为参考依据。     

肱骨近端三维解剖结构的测量分析

目的利用多层螺旋CT容积再现技术测量国人肱骨近端三维解剖结构核心参数,比较性别和侧别的差异,为研制适用于国人解剖结构特点的新一代肱骨近端假体提供参考。方法征集重庆地区正常成年志愿者100例,男59例,女41例;年龄21～57岁,平均40.4岁。经多层螺旋CT扫描双侧肩峰至肱骨滑车末端后,将信息传送到LEONARDO工作站。利用容积再现技术测量前后扭转角(retroversion angle,RA)、股骨头倾斜角(neck-shaft angle,NSA)、向内的偏心距(medial offset,MO)和向后的偏心距(posterior offset,PO)。将测量结果进行左右侧、男女性别间比较,并分析参数间相关性。结果 100例200侧肩关节RA为(19.9±10.6)°,NSA为(134.7±3.8)°,MO为(4.0±1.1)mm,PO为(2.6±1.3)mm。RA及MO左、右侧比较,差异有统计学意义(P<0.05);NSA及PO左、右侧比较,差异无统计学意义(P>0.05)。男性双侧肩关节RA及PO均大于女性(P<0.05),NSA及MO均相似(P>0.05)。PO和RA成正相关(r=0.617,P=0.000),MO和NSA无相关性(r=—0.124,P=0.081)。结论 RA及MO存在侧别差异,不能用对侧测量值作为模板;RA和PO存在性别差异。假体设计和肱骨近端重建时,需注意考虑以上因素。     

下颈椎椎弓根螺旋CT扫描的三维重建及测量

目的 评价应用多层螺旋CT扫描三维重建技术测量下颈椎椎弓根相关参数的可行性. 方法 8具成年男性颈椎标本经螺旋CT扫描后,把信息传送至随机工作站(Silicon Graphics O2),结合下颈椎榷弓根置钉的参数需求,进行三维重建[容积成像(VR)和多平面重组(MPR)]后测量椎弓根各个相关数据.然后对这些数据进行分析. 结果本组下颈椎椎弓根的外展角平均为42.02°±7.55°,C_7最小(35.63°±6.34°),C_4最大(46.94°±5.69°);头倾角平均为76.30°±12.01°,C_3最小(72.93°±6.57°),C,最大(81.27°±13.34°);入点至下关节缘距离平均为(11.23±1.78)mm,C_3最小[(10.54±1.25)mm],C_6最大[(12.05±1.40)mm];入点至侧块外缘距离各椎体相筹较大,平均为(2.65±1.21)mm,C_4最小[(1.69±0.81)mm],C_7最大[(3.74±0.99)mm];入点至椎体前缘距离各椎体差异较小,平均为(31.42±2.13)mm;椎弓根皮质骨高度平均为(8.43±1.30)mm,宽度半均为(5.54±1.26)mm;椎弓根松质骨高度平均为(3.69±1.19)mm,宽度平均为(2.67±1.15)mm;椎弓根皮质高度一般大于宽度,C_4内径最小,C_7内径最大. 结论 VR、MPR重建图像可满足椎弓根参数测量要求,其所测量的下颈椎椎弓根参数可满足经椎弓根手术的术前评估需求;下颈椎椎弓根变异较大.     

多层螺旋CT对胫骨平台骨折分型及治疗的临床价值

[目的]探讨多层螺旋CT(MSCT)容积重组技术(VRT)和多平面重建(MPR)在胫骨平台骨折(TPF)分型及治疗中的临床应用价值.[方法]2005年8月-2009年2月对45例49侧TPF患者的病例资料进行回顾性分析.其中男32例,女13例;年龄20～65岁(平均46岁).4例为双侧TPF.所有患者均行X线检查和64层螺旋CT扫描仪扫描.在轴位CT扫描后行VRT和MPR成像.按照Schatzker分型标准,应用X线片与64层螺旋CT扫描(包括VRT、MPR成像)分别进行分型和制定相应的治疗方案.[结果]参考VRT、MPR成像后,更改X线分型13侧(13/49)、更改治疗方案8侧(8/49)、发现胫骨髁问嵴骨折15侧(漏诊率46.9%)和腓骨近端骨折6例(漏诊率28.6%).[结论]MSCT(VRT+MPR)可以清晰显示TPF塌陷的范围和程度、细节及隐匿骨折,有助于骨折的正确分型、降低漏诊率和选择合理的治疗方案,是X线片和轴位CT扫描有效的补充手段,具有较高临床应用价值.     

Variations in the retroversion of the humeral head

It is generally accepted that the humeral head in adults is retroverted between 25 degrees and 35 degrees. To assess the validity of this belief, 336 dry bone specimens of humeral heads were measured. The specimens were taken from various ethnic groups: white Americans, black Americans, New Mexican Indians, northern Chinese, Alaskan Eskimos, and Negev Desert bedouins. There was significant variation in retroversion angle between specimens from different ethnic groups and even wider variation between specimens within particular groups--a finding contrary to popular belief. Retroversion angle in the specimens ranged from -8 degrees to +74 degrees. In addition, 50 fetal skeletons of white and black Americans were studied. The mean humeral head retroversion angle in the fetal skeletons was 78 degrees, much greater than that in adults. It was evident that the large retroversion angle in the very young decreases with growth and that it does so to a varying extent among different ethnic groups and individuals. It is of clinical importance to understand the variations in humeral head retroversion among individuals undergoing operation and the ways in which this parameter might be manipulated to surgical advantage.     

数字化技术辅助人工肱骨头置换术可行性研究

目的通过CT扫描尸体标本的方法探讨数字化技术辅助下利用自制的定位装置进行个性化人工肱骨头置换术的准确性及可行性。方法对10具双侧上肢尸体标本（包括肩、肘关节）进行CT扫描,利用数字化软件,根据CT扫描数据测量肱骨头高度及后倾角度;制造肱骨近端粉碎性骨折模型20例,运用自制的定位装置在人工肱骨头置换术中重建肱骨头的高度及后倾角度;术后再次测量并对数据进行统计学分析,比较术前术后相关参数的差异。结果 20例模型在人工肱骨头置换术中使用自行研制的定位装置均可有效控制假体高度及后倾角度,手术前测得肱骨头高度平均为（28.57±2.38）cm,肱骨头后倾角平均为（23.0°±5.8°）（11.1°~28.7°）。术后假体高度（t=0.185,P〉0.05）及后倾角度（t=0.481,P〉0.05）与术前相比其差异无统计学意义。结论在人工肱骨头置换术中利用自制的定位装置,可根据健侧测量的数据重建患侧的肱骨头的高度和后倾角度,做到真正的个性化设计和精确的肩关节置换。     

Computed tomography measurement of humeral head retroversion: Influence of patient positioning

For accurate humeral head arthroplasty, the surgeon needs to know some geometric data, such as, for example, the retroversion angle of the humeral head. Only a few reports have described and evaluated the use of computed tomography (CT) to measure humeral head retroversion. The humerus position relative to the roentgen beam is variable from one subject to another depending on the patients' morphology. It could influence the retroversion measurement and has not been investigated previously. This study analyzes in 9 cadaver humeri the variability of retroversion angle measurements with different humerus positioning relative to the roentgen beam during CT examination. The truest retroversion angle can be obtained when true axial slices, perpendicular to the humeral diaphysis, are obtained. Our study tries to clarify technical problems that occur during CT examination. Geometric considerations that can modify the measurements are presented. A reliable method of humeral head retroversion angle measurement is recommended, which could be useful to the shoulder surgeon.     

Biomechanical benefits of anterior offsetting of humeral head component in posteriorly unstable total shoulder arthroplasty: A cadaveric study

Restoration of joint stability during total shoulder arthroplasty can be challenging in the face of severe glenoid retroversion. A novel technique of humeral head component anterior‐offsetting has been proposed to address posterior instability. We evaluated the biomechanical benefits of this technique in cadaveric specimens. Total shoulder arthroplasty was performed in 14 cadaveric shoulders from 7 donors. Complementary shoulders were assigned to either 10° or 20° glenoid retroversion, with retroversion created by eccentric reaming. Two humeral head component offset positions were tested in each specimen: The anatomic (posterior) and anterior (reverse). With loads applied to the rotator cuff and deltoid, joint contact pressures and the force and energy required for posterior humeral head translation were measured. The force and energy required to displace the humeral head posteriorly increased significantly with the anterior offset position compared to the anatomic offset position. The joint contact pressures were significantly shifted anteriorly, and the joint contact area significantly increased with the anterior offset position. Anterior offsetting of the humeral head component increased the resistance to posterior humeral head translation, shifted joint contact pressures anteriorly, and increased joint contact area, thus, potentially increasing the joint stability in total shoulder arthroplasty with simulated glenoid retroversion. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:666–674, 2016.     

Why is the humeral retroversion of throwing athletes greater in dominant shoulders than in nondominant shoulders?

A rotation angle of the proximal humerus relative to the elbow (bicipital-forearm angle) was measured by use of ultrasonography to determine the relationship between humeral retroversion and growth in dominant and nondominant shoulders of 66 elementary and junior high school baseball players. The subjects were aged 12 years on average. The bicipital-forearm angle was significantly smaller in dominant shoulders than in nondominant shoulders. This indicated that the retroversion angle was greater in dominant shoulders than in nondominant shoulders. Furthermore, there was a moderately positive correlation between age and the bicipital-forearm angle in both dominant and nondominant shoulders. From these data, we conclude that the humeral retroversion angle decreases with age, and the decrease is much smaller in dominant shoulders. We assume that the repetitive throwing motion does not increase the retroversion of the humeral head but rather restricts the physiologic derotation process of the humeral head during growth.     

Determining humeral retroversion with computed tomography

BACKGROUND: The purpose of this study was to develop and standardize a technique in which computed tomography images are used to determine the humeral torsion angle with landmarks that can be used during surgery. METHODS: One hundred and twenty cadaveric humeri were studied. The retroversion of these anatomical specimens was measured on a computed tomography scan and compared with the direct measurements of the specimens. The retroversion of the humerus was measured by determining the orientation of the proximal articular surface of the humerus with respect to the transepicondylar line of the distal part of the humerus and the forearm axis. To evaluate this method of measuring retroversion, the protocol was tested in patients before and after shoulder arthroplasty. RESULTS: The degree of reproducibility of the measurements made on the computed tomography scan was evaluated by determining the interclass correlation coefficient. The interclass correlation coefficient was considered good (between 0.85 and 0.90) for the measurements of the normal humeri when the orientation of the articular surface measured in the distal part of the humeral head, the epicondylar axis, and the ulnar axis were used as references. There was a significant difference (p < 0.01) between the mean angular orientation of the proximal articular surface with respect to the epicondylar axis (17.6 degrees ) and the mean angular orientation of the proximal articular surface with respect to a line perpendicular to the forearm axis (28.8 degrees ). Despite a wide variation in the humeral torsion angle among the specimens from the different cadavera, the angle varied little between the two normal humeri of the same individual (mean side-to-side difference, 2.1 degrees ). CONCLUSION: This study demonstrated that retroversion of the proximal part of the humerus can be reliably measured with computed tomography. Clinical Relevance: Determining retroversion with computed tomography is more accurate than palpating the epicondylar axis or using the forearm as a goniometer during surgery. Computed tomography is useful for measuring the amount of rotation of humeri with a malunited fracture or severe arthritic deformity.     

CT Scan Method Accurately Assesses Humeral Head Retroversion

Humeral head retroversion is not well described with the literature controversial regarding accuracy of measurement methods and ranges of normal values. We therefore determined normal humeral head retroversion and assessed the measurement methods. We measured retroversion in 65 cadaveric humeri, including 52 paired specimens, using four methods: radiographic, computed tomography (CT) scan, computer-assisted, and direct methods. We also assessed the distance between the humeral head central axis and the bicipital groove. CT scan methods accurately measure humeral head retroversion, while radiographic methods do not. The retroversion with respect to the transepicondylar axis was 17.9° and 21.5° with respect to the trochlear tangent axis. The difference between the right and left humeri was 8.9°. The distance between the central axis of the humeral head and the bicipital groove was 7.0 mm and was consistent between right and left humeri. Humeral head retroversion may be most accurately obtained using the patient’s own anatomic landmarks or, if not, identifiable retroversion as measured by those landmarks on contralateral side or the bicipital groove. Each author certifies that he or she has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article.     

Computed tomography evaluation of shoulder prosthesis retroversion

Computed tomography (CT) allows calculation of anatomic and prosthetic humeral head retroversion. The purpose of this study was to demonstrate how the retroversion angle measured by CT scan varied with changes in arm position in the CT scan reference system. A trigonometric analysis shows that the measured retroversion angle decreases when the arm is in extension and increases when it is in flexion, compared with the true retroversion angle determined perioperatively. For the same degree of flexion, or extension, the error of measurement is greater when the initial true retroversion is low. A shoulder prosthesis with 20 degrees of true head retroversion was radiologically scanned with different degrees of flexion, extension, and abduction. The results validate the theoretical analysis. Trigonometric formulas are proposed to correct the retroversion angle measured by CT scan.     

Humeral head retroversion in competitive baseball players and its relationship to glenohumeral rotation range of motion

DESIGN: Prospective case series. OBJECTIVE: To determine if an osseous component in the form of increased humeral head retroversion may contribute to observed differences in the amount of rotation between the throwing and nonthrowing shoulders of competitive baseball players. BACKGROUND: Differences in side-to-side shoulder rotation range of motion (ROM) are seen in throwing athletes. In the past, these differences have been attributed to adaptive changes to the surrounding soft tissue structures, including attenuation of the anteroinferior capsule and ligaments, and tightening of the posterior capsule. Recent studies, however, suggest that a possible osseous adaptation in the form of increased humeral head retroversion may be the cause of this side-to-side ROM difference. bilateral computed tomography (CT) scans to determine the angle of humeral head version. Maximal shoulder internal and external rotation ROM at 90 degrees abduction were measured both passively and actively for both shoulders. RESULTS: Players had statistically significant (P<.001) side-to-side difference in humeral head version, with an average of 10.60 greater retroversion in their throwing arm compared to their nonthrowing arm. A significant side-to-side difference was not observed in the control group (average difference, 2.30; P = .197). Greater humeral head retroversion was associated with greater external rotation ROM and lesser internal rotation ROM in the throwing arm of the throwers. CONCLUSIONS: Our results indicated that highly competitive baseball players do have greater humeral head retroversion in their dominant arm, which can partially explain the observed differences in side-to-side shoulder rotation ROM.     

Proximal humeral osteotomy to correct the anatomy in patients with recurrent shoulder dislocations.

Surgical treatment of patients with traumatic shoulder dislocations is usually successful, but soft-tissue surgery in patients with nontraumatic shoulder dislocation often fails to stabilize the joint. Previous studies have shown that decreased humeral head retroversion might be one cause of anterior shoulder instability. Eleven patients with anterior recurrent dislocations, five traumatic and six nontraumatic, and all with a small humeral head retroversion angle, have been operated on using a proximal humerus osteotomy to correct the abnormal anatomy. After surgery, the humeral head retroversion was normalized to a mean angle of 34 degrees. All shoulders became stable. External rotation increased 7 degrees on the average, and internal rotation decreased 10 degrees on the average. One year after surgery, shoulder function was excellent in all operated shoulders.